Hello Gelmhirst,
Rogue originally placed those switches inside the chassis. It was only on the later production runs that the switches were placed on the back panel of the monoblocks.
According to an old "Stereophile" review of the M-120's, you have to remove the 6550 tubes in order to access the ultralinear/triode switches.
http://stereophile.com/tubepoweramps/735/index1.html
Hope this helps,
Jeff
Rogue originally placed those switches inside the chassis. It was only on the later production runs that the switches were placed on the back panel of the monoblocks.
According to an old "Stereophile" review of the M-120's, you have to remove the 6550 tubes in order to access the ultralinear/triode switches.
http://stereophile.com/tubepoweramps/735/index1.html
Hope this helps,
Jeff